Increasing patient-reported allergies are not associated with pain, functional outcomes, or satisfaction following medial patellofemoral ligament reconstruction: a retrospective comparative cohort study

Background: Patient-reported allergies (PRAs) are often stigmatized as a potential nonmodifiable risk factor for increased pain and worse functional outcomes following surgery. However, there is a dearth of literature directly assessing the impact of PRAs on outcomes in sport surgeries such as medial patellofemoral ligament reconstruction (MPFLR). The purpose of our study was to determine whether PRAs were associated with worse outcomes following MPFLR. Methods: We conducted a retrospective review of patients who underwent MPFLR at our institution from 2011 to 2019. Patients were included if they had at least 12 months of follow-up. PRAs were obtained from preoperative medical assessments and categorized by drug class. Demographic and perioperative data were obtained from electronic medical records. Postoperative outcomes were measured using a telephone survey and included recurrent instability, Visual analog scale (VAS) for pain, VAS for sports, Kujala score, MPFL-Return to Sport after Injury (MPFL-RSI) score, and overall satisfaction score. Multiple linear regression was used to determine association between PRAs and outcome measures, and p-values less than 0.05 were considered significant. Results: The cohort included 141 MPFLR. Most patients were female (98, 70%) with an average age of 25 years (range 12–56 years). Average follow-up time was 47 months. Forty-seven patients (33%) reported at least one PRA. There were no significant differences in postoperative pain, functional outcomes, satisfaction, or return to sport between patients with or without PRAs (all p > 0.05). Absence of antibiotic PRAs was predictive of higher VAS (p < 0.007), but there were no other differences. There were no significant differences in outcomes between patients without PRAs, PRAs without a concomitant psychiatric disorder, or PRAs with a concomitant psychiatric disorder (all p > 0.05). Conclusions: In conclusion, PRAs with or without concomitant psychiatric diagnoses are not associated with worse postoperative pain, functional outcomes, or satisfaction following MPFLR with allograft, dispelling common misconceptions that increased number of allergies or psychiatric diagnoses lead to inferior surgical outcomes. Presence of antibiotic allergies was associated with lower VAS postoperative pain score. Future research should investigate the relationship between PRAs and other surgeries in the field of sports medicine.